3C 263
Quasar in Ursa Major
From Wikipedia, the free encyclopedia
3C 263 is a radio-loud, lobe-dominated quasar located in the constellation of Ursa Major. It has a redshift of (z) 0.652[1] and was discovered in 1966 by astronomers.[2] It is known to show evidence of superluminal motion[3] and is located inside the center of a moderate rich galaxy cluster.[4]
| 3C 263 | |
|---|---|
The quasar 3C 263. | |
| Observation data (J2000.0 epoch) | |
| Constellation | Ursa Major |
| Right ascension | 11h 39m 57.0250s |
| Declination | +65° 47′ 49.482″ |
| Redshift | 0.646000 |
| Heliocentric radial velocity | 193,666 km/s |
| Distance | 5.817 Gly |
| Apparent magnitude (V) | 16.32 |
| Apparent magnitude (B) | 16.50 |
| Characteristics | |
| Type | Opt.var; Sy1, LPQ |
| Other designations | |
| DA 305, 4C 66.13, LEDA 2817636, 2E 2503, PG 1137+660, QSO B1137+660, RBS 1014 | |
Description
3C 263 is classified as a Fanaroff-Riley Type II source.[5][6] It is also a steep spectrum[7] source with its radio structure best described as a double-lobed structure.[8] When imaged by Very Large Array, its lobes are asymmetrically placed and of unequal brightness. One lobe is described as jetted and the other as being relaxed. There is also a linear jet containing bright, elongated knots and a diffused emission region located 2 arcseconds from the hotspot region.[9] There is another weak component showing a flux density of 0.13 × 10−26 W m−2 Hz−1.[10]
Observations by Chandra X-ray Observatory, showed the compact component of the quasar is made up of several subcomponents; mainly an extended halo, a weak leading component and a bright central component with a flat two-point radio spectrum.[5] Parsec-scale observations showed the source as a core-jet structure with a bright nucleus. Based on results, its jet contains three knots which in turn projects out from the radio core by 2.5 mas.[11]
The nucleus of 3C 263 is found variable. It exhibits an variation amplitude that is greater than 40 mJy at 5 GHz. Superluminal motion was also detected inside its nucleus with evidence of parsec-scale jet components showing acceleration and nonradial motion. According to results, the inner jet component has a transverse velocity of 0.7h−1 c while the outer jet component has a velocity of 1.2-2.5 h−1 c.[3] Soft X-ray emission was also found surrounding the object with its luminosity calculated as 16.4 × 1043 erg s−1.[12]
The host galaxy of 3C 263 is described as a flat-system according to Hubble Space Telescope. Based on observations, the host has an aligned major axis along the position angle of 350°. The absolute magnitude of the host is approximately 22.2.[13] Faint galaxies have also been found surrounding the object.[14] A multiphase absorption system was found at redshift (z) 0.32566 towards the object, showing detections of neon elements.[15][16]